Telephone system.



' LE ROY W. STANTON.

TELEPHONE SYSTEM.

APPLICATION FILED JUNE 26, 1916.

1,224,425. Patented May 1, 1 917 UNITED STATES PATENT orricn.

LE ROY W. STANTON, OF DAVENPORT, IOWA.

TELEPHONE SYSTEM.

To all tuhom it may concern:

Be it known that I, LE ROYWVSTAN TON,

'a citizen of the United States, residing at of an operator at an exchange. The invention is herein disclosed inits application to a polystation system wherein subscribers on v a single line are selectively signaled. It is also shown as applied to a simple manual system.- The invention, however, is capable of more extended use and-I therefore do not wish to be limited in this regard. The form chosen for the-present disclosure is merely typical. will be more fully understood upon refer-- ence to the following detailed description taken in connection with the accompanying drawing, and the scope of the invention will be particularly pointed out in the appended claims.

I In the drawing, Figure 1 is a diagram of a telephone system embodying the present invention, and Fig. 2 is a detailed view of plug and jack contacts. In these two ,figures like characters refer to like parts.

In the diagram a substation 10 is connected by linelimbs 11 and 12 to an exchange where the line is provided with answering jack 13 and multiple jacks, of which one designated 14 isshown. The line is also provided with the usual line relay 15, a cutoff relay 16 and line lamp 17. As shown in the diagram, this line is a. calling line. The called line of the diagram, which includes limbs 18 and 19, extends to the central ofiice from substations 20, 21, 22 and 23, the line being a polystation or party line. In this instance the line-is provided with acks 24:, 25,26 and 27, which correspond to the substations on the line and are to be respectively used according tothe particular substation which is to be signaled. The line is provided withthe usual cut-off relay 28 line relay 29 and line lamp 30. Connection is established between the jacks of the lines Specification of Letters Patent.

Application filed June 26, 1916. Serial No. 105,891.

The exact nature of the invention Patented May 1, 1917.

by means of a cordcircuit terminating at one end in a plug 31 and at the other end' in a plug 32, and having connecting strands 33 and 34 Condensers 35 and 36 are interposed 1n these strands in the usual way. Th1s cord circuit is provided with-supervisory relays 37 and 38, which control supervlsory lamp 39, and supervisory relays 40 v and 11, which control supervisory lamp 42.

An operators 'set 13 is adapted to be in-.

cludedin circuitv by a listening key 41 1, and test relay 4 5 is brought into circuit during the testing operation. In addition, the cord circuit .is provided with ringing relays 4:6, 47, 18 and 49, which are under the control of a relay 50 and operate to bring -into circuit generators 51, 52, 53 and 54, severally, according to the particular substation 20, 2 1, 22 or 23, which is to be signaled.

With this description ofthe apparatus we may now pass to a description of the operation of the system and this description will bring in other circuits and parts which will be therein sufliciently' understood without further preliminary description. If we assume that the party at substation 10'removes his receiver 55 from its hook 56 in the act .of initiating a call, it will be seen that he will close a circuitwhich may betraced to ground from out off relay contact 57, line limb 12, transmitter 58, switch hook 56, coil 59, line limb 11, winding. of line relay 15 and battery 60 to ground. This will close the local circuit for lamp 17 through battery 61 and contact 62. I

The next act of'the operator is to'insert plug 31 into answering jack 13. a When this is done a circuit is closed from battery 63 throughthe winding of supervisory relay 38, strand 34, plug-and jack sleeve contacts, and the winding of cut-off relay 16 'to ground. In addition to this path a path in parallel to that through the winding of relay 16 is provided over-cut-oif alternate contact 64 through 'line limb l1, coil 59, switch hook 56, transmitter 58, line limb 12, alternate contact 57, plug and jack tip contacts, the winding of supervisory relay 37, to ground. The closing of this latter path energizes supervisory relay 37 and by opening its normally closed contact 65 prevents the lighting of supervisory lamp 39 upon the closure ofcontact 66 of relay 38. The closing of thepath through cut off relay 16 line, she depresses her listening key it and contacts 70, (39, (SS, plug and jack tip conbringsher operating set 43 into circuit and tacts, alternate contact 81, line limb 18, receives the order from the calling party. thence in parallel through the substations I it be assumed that the calling party de- 20, 21, 22 and and back to the exchange sires to converse with a party at substation over line limb l9, thence through alternate 75 20, and that the generator 51 is the generacontact 82, plug and jack sleeve contacts, tor corresponding to substation :20, that is a normal contacts 83, Si and S5 of ringing regenerator which will give the requisite he lays l9, *8 and 47, respectively, alternate quency to ring the bell at substation 20, then contact 86 of relay l6, resistance 87 and batthe operator will touch the tip of plug 32 tery S8 to 'round. At the same time cur- 33 against test contact 67 of jack :27 and if the rent will Tow from battery 88 over the line is in use there will be a potential above sleeve side of the circuit just traced through that of normal upon the contact 67, by reathe winding of cut-ofi' relay to ground, so as son of the connection of the sleeve side of to hold the latter energized when the supply the circuit with battery through the sleeve from battery 63 is cut oil. It may be noted 5 strand of the other cord circuit which is conthat the path for ringing current through nected to the line. In case of finding such a the substations 20, .21, 22 and is the same potential upon the test contact 67 of the in each case, but thatlthe only bell which is jack 2?, there will be a momentary flow of rung is that which is tuned to the frequency 25 current through the tip of plug 32, normal of the particular generator in circuit. Con- 9. contacts (38. (59. T0, T1 and T2, and the windsequently undim the assumptions here made ing of relay to to ground. The closing of the only bell which will be rung when genthis circuit will momentarily energize relay erator 51 is in circuit is that at substation 45 and, by closing its contact 13, momen- 20. This path for ringing current may be 0 tarily complete a path by which current will traced in the latter instance from line limb 5 how from battery 74 through the tertiary 18 through call bell S9, switch hook 90 and winding of the induction coil of the operacondenser 91 to line limb 19. It may also tor's set to ground. The result will be a be noted that when the plug 32 is inserted momentary click in the receiver, by which in jack 3?, not only was cut-oil relay 2Q en- 35 the operator will be advised of the busy ergized, but the sleeve supervisory relay i1 190 condition of the line tested. If such condiwas also energized by reason of a circuit tion be found she will advise the calling closed from battery 63 through the winding party and he will restore his receiver to its of relay l1 over the sleeve side of the cirhook and the operator will withdraw the cuit and through the winding of cut-oil replug 31 and all the parts will be left in norlay to ground. The closing of this circuit 105 mal condition awaiting a further call. upon the insertion of plug 32 into jack :27,

In case the line is found to be idle upon by energizing relayv l1, closes contact 9'2 the test, the plug 232 is inserted into jack 2? and thereby brings supervisory lamp l2 and the tip and sleeve contacts of the jack into circuit. This lamp remains lighted engage the tip and sleeve strands of the line. until the tip SI IPQI'VlSOIy relay is energized. 0

These tip and sleeve contacts form a path The interrupter 80 by making and breakfor the talking current at this point. The ing the circuit through the ringing relay l6 third contact 75 of the plug 232 at this time alternately connects ringing current to the engages ringing contact 76 of jack QT and line and disconnects the. same from it.

thereupon closes a local circuit which will When the interrupter is in open position 115 automatically apply the aroper ringing curthe generator 51 is disconnected at contact rent'to the line to signal the party at sub- T1 but at this time the tip strand 33 of the station 20. It will be noted that when the cord circuit is completed through to the tip plug 32 was inserted into jack :2? that the supervisory relay l0. If at the time this 55 cut-oil relay 28 was drawn up and the line path is closed at contact T1, the party at sub- 12 limbs 15 and 10 extended to the tip and station 20 removes his receiver from its' sleeve contacts of the jack just as in the case hook. or as soon thereafter as contact 71 re of the line limbs 11 and 12 as previously deturns to its normal position. current will scribed. The path closed as a result of flow through the substation and back over the engagement of plug and jack contacts the line to operate the tip relay 40. The 75 and 76 may be traced from contact 76 path for this How of current may be traced through conductor 7?, battery 78 winding from alternate contact 82 of cut-off relay of relay 46, normal contact 79 of relay 50, 28, through line limb 19, coil 93. switch hook interrupter S0 and contact 75, to the starting 90, transmitter 94, line limb 1S, alternate 65 point contact 76. The closing of this cir contact 81, .plug and jack tip contacts, norcuts oii the line relay 15'and extinguishes line lamp 17, and extends the line limbs 11 and 12 to the terminals of the jack.

As soon as the operator has inserted the answering plug into the jack of the calling cuit energizes relay 4.6 and immediately connects the ringing generator 51 into circuit with the called line. The path for ringing current extends from the live pole of generator 51 through alternate contact 71, normal mal contacts 68,. '89, "T0 and T 1, alternate con- At the same time supervisory relay 40 will close a circuit for the winding 96 of relay 50 through closed contact 97 of relay 40 to ground. This circuit will be supplied with current from battery 97 and as soon as relay 50 is energized a locking circuit wlll be provided through the locking winding 98 and closed contact 99 of relay 50 and closed contact 100 of relay 41 to ground. The energization of relay 50 will open contact 79' and thereby de'elnergize ringing relay 46 and pre vent the further-application of ringing cur rent to the called line.

It will be noted that the interrupter 8 0 and the contact 79 are in.a branch which is common to the parallel branches through the windings of ringing relays 46, 47 48 and 49, and consequently when this common portion of the circuit is interrupted at contact 79 it will be impossible for any ofthe ringing relays to be energized.

During conversation the transm1tters Will be supplied with current from the battery 63 through the supervisory relays and the cord circuit strands out over the line in the usual way. It willbe noted that the locking circuit for relay 50 extends through-contact 100 of sleeve supervisory relay 41 and consequently it will-be impossible to deenergize relay' 50 until relay 41 has been denergiaed. This will only take place upon the withdrawal of the plug 32 from the assoc1ated 'ack.

-'If it had been desired to call some other substation then one of the otherjacks 24, 25 or 26 would have been used, and in suchcase local circuits would have been closed through the appropriate ringing relay. The

and 42 in the usual way and the operator takes down the connection by withdrawing the plugs 31 and 32 from their jacks. VWhen a this is done the line circuits assume their normal condition, which is that illustrated. Likewise the relay 41 becomes denergized and thereby releases relay 50 and the various parts of the cord circuit assume their normal condition, which is alm that illustrated.

In operating a system constructed in accordance with the present invention, the

operator does not need to use ringing keys,

but there is a jack available to her'"which" corresponds exactly witlfa'" desired station. Knowing that she wants a particular station she inserts the plug into the jack corresponding to that station.

That I claim as new and desire to secure by Letters Patent of the United States is:

1. A telephone system'comprising a poly station line; a plurality of connection terminals associated with said line; a link circuit; a connection terminal for connecting said link circuit to said line through any one of said connection. terminals; a plurality of sources of ringing current, each being in dividual to one of the stations on said line;

connections for operatively connecting said sources to said link circuit; relays for controlling said connections, ea'ch relay corresponding to and being usable only with one of said line connection terminals; and additional connections. whereby said relays are operated individually according to the particular line connection terminal used in connecting the link circuit to the line.

2. A telephone system comprising a polystation line, a plurality of connection terminals associated with said line, a link circuit, a connection terminal forconnecting said link circuit to said line through any one of said connection terminals, a plurality of sources of ringing current, connections for individually connecting each of said sources to said link circuit, a relay individual to each of said. sources and operative only to control the connections of the particular associated source, and additional connections whereby said relays are individuallyand selectively operated according to the particular line connection terminal. used in connecting the link circuit to the line.

3. A telephone system comprising a polystation line, a plurality of connection terminals associated with said line, a link circuit, a connection terminal for connecting said link circuit to said line through any one of said connection terminals, connections for providing a local. circuit for each of said line connection terminals, a ringing relay in each of said local circuits, sources of ringing current corresponding to said ringing relays, and connections for bringing each of said sources into circuit with the connected line when the corresponding ringing relay is energized.

4.'A telephone system including a telephone line of two conductors, substation apparatus, a link circuit having two talking conductors, tip and sleeve terminal contacts for uniting the conductors respectively of said lllfif and link circuit, tip and sleeve re-' lays a nterposed battery in bridge of said kin .onductors, a ringmg source, means for connecting said source 1n circuit with said line conductors when connected to said link circuit talking conductors, a relay and connections for controllingsaid means, and connections for controlling said latter relay which are controlled in turn by said tip and sleeve relays.

5. A telephone system comprising a telephone line of two limbs, a link circuit of two strandsfor connecting with said line, a ringing relay actuated in response to the connection of said line and link circuit, a source of ringing current connected to said line by the actuation of said ringing relay. a control relay for varying the circuit of said ringing relay, and a pair of relays for in turn controlling said control rclay, said pair of relays being connected one to one of said link circuit strands and the other to the other and one being controllable over said line and one of said strands and the other being controllable over a local circuit including a portion of the other of said strands and a portion of a limb of the connected line.

In testimony whereof I have hereunto subscribed my name this 24th day of June,

LE ROY \V. STANTFN.

Copies of this patent may be obtained for five cents each, by addressing the Gommluloner of Patents, Washington, D. 0. 

